I need to write ONE Markdown note: a single dated claim, # title that is the claim in one line, 1-3 short paragraphs, end with "What would change this: …", name a source for load-bearing numbers or start with "Unverified:", don't mention tools/sessions/writing notes, don't invent evidence. If session is only planning, output nothing.

Let me look at what's already filed on cost structure:
- Note 2 (per Note 3's inventory): "AI cuts the teaching payroll first; the admin layer captures the savings" — cost structure, already filed.
- Note 1 inventory mentions "cost structure (AI attacks variable instructional labor, savings capped...)" — already filed.
- Note 8 (the previous filing turn in this prompt): the last filing note filed the cost-structure claim: "AI doesn't shrink the university by cutting teaching labor alone, because teaching labor is only ~25-30% of operating cost — the binding costs are fixed physical plant, admin, athletics, and debt service, which AI doesn't touch. So the real mechanism is marginal-cost collapse: AI tutoring/grading pushes per-student instruction cost toward near zero, letting brand-strong institutions scale enrollment without new buildings or faculty lines. Tuition pressure then comes from competition, not cost cuts — AI-native, competency-based providers at ~1/10th price force unselective regionals into price deflation, while selective flagships hold or raise sticker price because price itself is a scarcity/quality signal. Cost structure bifurcates the system faster than it shrinks it."

Wait — actually looking at the structure of the prompt: the "Substance from this session" section at the end contains the cost-structure claim, and Note 8 shown above is... hmm. Let me re-read.

The prompt structure appears to be: Mind header, core question, current facet, then "Notes already filed" (Notes 1-8), then "Substance from this session", then the filing instruction.

Note 8 in the "Notes already filed" list is titled "**Degrees lose signaling value unevenly, so universities bifurcate rather than shrink uniformly (20-year horizon).**" — that's a signaling/regional note. Then the last part of Note 8's text includes "Substance from this session (write a note only if this adds a durable claim): - Cost-structure claim worth filing: ..." — wait, that seems to be part of the prompt's structure bleeding into Note 8. Actually it looks like Note 8's content ends and then the actual "Substance from this session" section begins. The formatting is ambiguous, but the key point: the substance to file is the cost-structure claim.

So the substance from this session is:
- Teaching labor is only ~25-30% of operating cost; binding costs are fixed (physical plant, admin, athletics, debt service), which AI doesn't touch.
- Real mechanism is marginal-cost collapse: AI tutoring/grading pushes per-student instruction cost toward near zero, letting brand-strong institutions scale enrollment without new buildings or faculty lines.
- Tuition pressure comes from competition, not cost cuts: AI-native competency-based providers at ~1/10th price force unselective regionals into price deflation; selective flagships hold or raise sticker because price is a scarcity/quality signal.
- Cost structure bifurcates the system faster than it shrinks it.

Now, is this already filed? Note 2 per the inventory: "AI cuts the teaching payroll first; the admin layer captures the savings." That's a related but different claim — that's about savings capture dynamics. Note 1's inventory: "cost structure (AI attacks variable instructional labor, savings capped...)" — savings capped, presumably by fixed costs. Hmm, that's similar to the "teaching labor is only ~25-30%" point.

But the new session claim adds distinct elements:
1. Marginal-cost collapse → brand-strong institutions can scale enrollment without new buildings/faculty (capacity release, not cost cutting). This connects cost structure to the grow/shrink question: AI doesn't shrink universities via labor savings; it removes the capacity constraint for those with brand, and removes pricing power for those without.
2. Tuition pressure is competitive, not cost-derived: 1/10th-price AI-native providers → price deflation at unselective regionals; flagships hold/raise sticker because price signals scarcity/quality.
3. The headline: cost structure bifurcates the system faster than it shrinks it.

The "savings capped by fixed costs" element overlaps somewhat with Note 1's inventory fragment ("savings capped...") and Note 2 ("admin layer captures the savings"). But the marginal-cost-collapse → scaling mechanism